Jim,
I looked up "ideal diodes", which are in fact MOSFETs, that would keep your batteries isolated in future. The one I found, 2 diodes rather than a bridge, have forward voltage drop at 15A of 0.075V. Not a very high current rating, but here is an example: Traditional diode at 15A drops 0.6v and cooks at (15)x(0.6) = 9Watts, whereas the ideal type consume (15)x(0.075) =1.125Watts - meaningfully lower power and voltage loss, and less chance that they themselves will initiate a heat problem.
The ideal diodes are at MPJA.com (or Marlin P Jones as was) and are $5 including heat sink!! Stock No: 35486 DI. I will keep serching for a higher rated set.Cheers, Paul